EOD Primary Tumor


**Note 1:** The tentorium cerebelli is an extension of the dura mater that separates the cerebellum from the inferior portion of the occipital lobes. The location of the tumor above or below the tentorium can help in determining the type of tumor; also most adult brain tumors are supratentorial, and most pediatric brain tumors are infratentorial. In the following list, note that ICD-O-3 codes C71.0 and C71.9 include both supratentorial and infratentorial subsites. **Infratentorial sites by ICD-O-3 codes** C710: Hypothalamus, pallium, thalamus C716-C717 **Supratentorial sites by ICD-O-3 codes** C710, except hypothalamus, pallium, thalamus C711-C715 C718: Corpus callosum, tapetum C719: Anterior cranial fossa, middle cranial fossa, suprasellar **Note 2:** Discontiguous spread, including circulating cells in cerebrospinal fluid (CSF), is coded in EOD Mets.
Code Description SS2018 T
050 Benign or borderline brain tumor B
100 Infratentorial tumor confined to - Brain stem or meninges of brain stem (one side) + Medulla oblongata + Midbrain (mesencephalon) + Pons - Cerebellum or meninges of cerebellum (one side or midline) + Lateral lobes + Median lobe of cerebellum + Vermis - Hypothalamus - Thalamus Infratentorial tumor - Both cerebellum and brain stem involved with tumor on one side Supratentorial tumor confined to - Cerebral hemisphere (cerebrum) or meninges of cerebral hemisphere (one side) + Frontal lobe + Occipital lobe + Parietal lobe + Temporal lobe Confined to ventricles Tumor invades or encroaches upon ventricular system Confined to brain, NOS Confined to meninges, NOS L
500 Tumor crosses the midline Bone (skull) Contralateral hemisphere Corpus callosum (including splenium) Major blood vessel(s) Meninges (e.g., dura) Nerves (cranial, NOS) Spinal cord/canal Supratentorial tumor extends infratentorially to involve - Brain stem - Cerebellum - Hypothalamus - Pallium - Posterior cranial fossa - Thalamus Infratentorial tumor extends supratentorially to involve - Cerebrum (cerebral hemisphere) (excluding hypothalamus, pallium, thalamus) - Anterior cranial fossa - Corpus callosum - Middle cranial fossa - Suprasellar brain - Tapetum RE
700 Circulating cells in cerebral spinal fluid (CSF) Nasal cavity Nasopharynx Other direct extension outside CNS Posterior pharynx Further contiguous extension D
800 No evidence of primary tumor U
999 Unknown; extension not stated Primary tumor cannot be assessed Not documented in patient record Death Certificate Only U
(1) Fritz AG, Ries LAG (eds). **SEER Extent of Disease 1988: Codes and Coding Instructions (3rd Edition, 1998)**, National Cancer Institute, NIH Pub. No. 98-2313, Bethesda, MD, 1998 (2) Young JL Jr, Roffers SD, Ries LAG, Fritz AG, Hurlbut AA (eds.). **SEER Summary Staging Manual-2000: Codes and Coding Instructions**, National Cancer Institute, NIH Pub. No. 01-4969, Bethesda, MD, 2001. (3) Collaborative Stage Work Group of the American Joint Committee on Cancer. **Collaborative Stage Data Collection System User Documentation and Coding Instructions, version 02.05**. American Joint Committee on Cancer (Chicago, IL) (4) Laws, E.R., Curran, W.J., et al. **Brain and Spinal Cord**. In: Amin, M.B., Edge, S.B., Greene, F.L., et al. (Eds.) AJCC Cancer Staging Manual. 8th Ed. New York: Springer; 2017: 857-869